    <?php  
    /* 
     * 使用:  
     * $page = new Page(连接符,查询语句,当前页码,每页大小,页码符)  
     * 连接符:一个MYSQL连接标识符,如果该参数留空,则使用最近一个连接  
     * 查询语句:SQL语句  
     * 当前页码:指定当前是第几页  
     * 每页大小:每页显示的记录数  
     * 页码符:指定当前页面URL格式  
     *   
     * 使用例子:  
     * $sql = "select * from aa";  
     * $page = new Page($conn,$sql,$_GET['page'],4,"?page=");  
     * 
     * 获得当前页码  
     * $page->page;  
     *   
     * 获得总页数  
     * $page->pageCount;  
     *   
     * 获得总记录数  
     * $page->rowCount;  
     *   
     * 获得本页记录数  
     * $page->listSize;  
     *   
     * 获得记录集  
     * $page->list;  
     * 记录集是一个2维数组,例:list[0]['id']访问第一条记录的id字段值.  
     *   
     * 获得页码列表  
     * $page->getPageList();  
     */  
      
    class Page  
    {  
        //基础数据  
        var $sql;  
        var $page;  
        var $pageSize;  
        var $pageStr;  
      
        //统计数据  
        var $pageCount; //页数  
        var $rowCount;  //记录数  
          
        //结果数据  
        var $list = array();  //结果行数组  
        var $listSize ;  
        //构造函数  
        function Page($conn,$sql_in,$page_in,$pageSize_in,$pageStr_in)  
        {  
            $this->sql = $sql_in;  
            $this->page = intval($page_in);  
            $this->pageSize = $pageSize_in;  
            $this->pageStr = $pageStr_in;  
              
            //页码为空或小于1的处理  
            if(!$this->page||$this->page<1)  
            {  
                $this->page = 1;  
            }  
              
            //查询总记录数  
            $rowCountSql = preg_replace("/([\w\W]*?select)([\w\W]*?)(from[\w\W]*?)/i","$1 count(0) $3",$this->sql);  
            if(!$conn)  
                $rs = mysql_query($rowCountSql) or die("bnc.page: error on getting rowCount.");  
            else  
                $rs = mysql_query($rowCountSql,$conn) or die("bnc.page: error on getting rowCount.");  
            $rowCountRow = mysql_fetch_row($rs);  
            $this->rowCount=$rowCountRow[0];  
            //计算总页数  
            if($this->rowCount%$this->pageSize==0)  
                $this->pageCount = intval($this->rowCount/$this->pageSize);  
            else  
                $this->pageCount = intval($this->rowCount/$this->pageSize)+1;  
              
            //SQL偏移量  
            $offset = ($this->page-1)*$this->pageSize;  
            if(!$conn)  
                $rs = mysql_query($this->sql." limit $offset,".$this->pageSize) or die("bnc.page: error on listing.");  
            else  
                $rs = mysql_query($this->sql." limit $offset,".$this->pageSize,$conn) or die("bnc.page: error on listing.");  
            while($row=mysql_fetch_array($rs))  
            {  
                $this->list[]=$row;  
            }  
            $this->listSize = count($this->list);  
      
        }  
          
        /* 
         * getPageList方法生成一个较简单的页码列表 
         * 如果需要定制页码列表,可以修改这里的代码,或者使用总页数/总记录数等信息进行计算生成. 
         */  
        function getPageList()  
        {  
            $firstPage;  
            $previousPage;  
            $pageList;  
            $nextPage;  
            $lastPage;  
            $currentPage;  
              
            //如果页码>1则显示首页连接  
            if($this->page>1)  
            {  
                $firstPage = "<a href=\"".$this->pageStr."1\">首页</a>";  
            }  
            //如果页码>1则显示上一页连接  
            if($this->page>1)  
            {  
                $previousPage = "<a href=\"".$this->pageStr.($this->page-1)."\">上一页</a>";  
            }  
            //如果没到尾页则显示下一页连接  
            if($this->page<$this->pageCount)  
            {  
                $nextPage = "<a href=\"".$this->pageStr.($this->page+1)."\">下一页</a>";  
            }     
            //如果没到尾页则显示尾页连接  
            if($this->page<$this->pageCount)  
            {  
                $lastPage = "<a href=\"".$this->pageStr.$this->pageCount."\">尾页</a>";  
            }  
            //所有页码列表  
            for($counter=1;$counter<=$this->pageCount;$counter++)  
            {  
                if($this->page == $counter)  
                {  
                    $currentPage = "<b>".$counter."</b>";  
                }  
                else  
                {  
                    $currentPage = " "."<a href=\"".$this->pageStr.$counter."\">".$counter."</a>"." ";  
                }  
                $pageList .= $currentPage;  
            }  
              
            return $firstPage." ".$previousPage." ".$pageList." ".$nextPage." ".$lastPage." ";  
        }  
      
      
    }  
      
      
    ?>  